Portable incubator



OGL 7, 1969 s. B. GITTELSON 3,470,866

PORTABLE INCUBATOR Filed Nov. 1e, 1966 s sheetss11eet 1 Z7 f j WAH4ms/fm' 0%./ y l ifm/Way- Oct. 7, 1969 s. B. GITTELSON 3,470,866

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' PORTABLE INCUBATOR Filed NOV. 16, 1966 3 Sheets-Sheet 5 w l Ilf 'IlmUnited States Patent O 3,470,866 PORTABLE INCUBATOR Stanley B.Gittelson, 1445 Merrick Ave., Merrick, N.Y. 11566 Filed Nov. 16, 1966,Ser. No. 594,891 Int. Cl. A61b 19/00; A01k 31/14 U.S. Cl. 128--1 6Claims ABSTRACT F THE DISCLOSURE This invention concerns a portableincubator for infants, of novel construction designed to enclose theinfant within a radiantly heated atmosphere having precisely controlledconditions within predetermined ranges and, when necessary the properdegree of oxygen enrichment.

The following is given as background:

Under usual nursery conditions, radiant loss accounts for approximatelytwo-thirds of the total heat loss of an infant. The effects of radiationlosses are of considerable importance in the establishment of neutralthermal conditions. The temperature measured in incubators is theambient air; since radiation is a function not of air temperature but ofthe surrounding objects (incubator wall, room wall, windows, etc.),losses by this means are not taken into consideration merely bymeasuring incubator air temperature. The effects of radiation can beshown by two examples: if `an incubator wall is chilled by proximity toan air conditioner or, more commonly, to a window at night, a baby canlose considerable heat despite a constant warm incubator airtemperature; conversely, hyperthermia readily occurs with little or nochange in air temperature if an infant is inadvertently placed in thesunlight.

An important difference between the infant and adult is the greaterthermal conductance of the infant. This is apparently due to less tissueinsulation, not to a difference in vasometer control, since thevasometer response to the cold has been shown to be well developed innewborn infants and animals. The Jeffect of an increased thermalconductance is a warmer skin temperature which in turn, results ingreater heat loss by convection and radiation. Because of the relativelylarge surface area and the increased thermal conductance, the neutraltemperature for infants is higher than for adults at otherwisecomparable environmental conditions.

In recent years careful studies of survival rates have demonstrated theimportance of maintaining normal skin temperature with infants of lowbirth weight, with respiratory distress syndrome or other disease stateswhere further metabolic stress is to be avoided. Important too, may beprecise control of body temperature in the delivery room and duringtransport to the nursery.

At present, many infants falling into these categories are transportedby an ambulance to certain medical centers which specialize in theircare. A trip by ambulance to such a medical center may involve one totwo hours. In cool weather, despite a heated ambulance and previouslyknown portable carriers these babies may arrive at their destinationwith body temperature down to a highly dangerous F.

As hereinbefore stated, the problem is that two-thirds of the heat lossin the infant is due to radiant heat loss because of large relative bodysurface area, poor body insulation and the inability of infants for acertain period to increase their ability to produce enough heat bythemselves to sustain life.

The need for a properly designed highly effective portable incubator forthe transportation of infants has existed for a long time. The presentinvention provides a highly effective portable incubator of novelconstruction which satisiies this need.

Among the objects of this invention are: To provide a highly effectivelightweight portable incubator which maintains the temperature of thewalls and roof of the container surrounding the infant duringtransportation at about 93.4 F. while maintaining the infants skin temperature at 96 F. and the ambient or air temperature in the container atabout 89 F. but not exceeding 93.2 F.; to provide a portable infantcarrier which is designed to be heated during transportation and whosewalls and roof are made of thin sheet metal, such as aluminum, havingthe characteristics of rapid heat conduction and excellent heatreflecting surfaces, surrounded by light weight plastic insulation suchas styrene or vacucel; to provide a portable relatively light weightincubator having an outer container or box provided with sheet metalwalls, and an inner infant carrying container or box provided with sheetmetal walls and roof, both containers being surrounded by insulation andadapted to be separately heated from different sources of electricenergy, and with the inner container fitted with suitable temperaturesensing devices; to enable the safe transportation of an infant over arelatively long period of time by means of a portable incubatorproviding a confined atmosphere having controlled conditions of wall andambient temperatures.

Briefly stated, the invention comprises a portable light weight infantincubator having an outer and a removable inner container both providedwith separate heat sources. The outer container has four thin sheetmetal walls and a bottom provided with a heat source or upon which aheating source is adapted to rest. The inner container in which theinfant is placed rests upon the interior bottom surface of the outercontainer and is provided with four walls and a cover or lid .all madeof thin sheet metal and all in good thermal conductive contact with oneanother. The sheet metal used in both containers is capable of rapidheat conduction and has excellent heat reflecting surfaces therebyproviding radiant heat to the interior of the container. One such metalis highly polished aluminum. The inner container is also provided with aheat source, such as an elongated resistance wire mounted on the coveror lid and adapted to be energized from a battery. Both inner and outercontainers are separately provided with heat insulation on the outsidesthereof, such as by lightweight plastic material containing air cellstherein. Temperature sensing devices are used to indicate the wall andambient temperatures of the inner container and means are provided formaintaining these temperatures within a desired range. The outercontainer is provided with a cover, preferably hinged to the top of oneside wall, and a handle for enabling the complete incubator includingboth cotnainers to be carried by hand.

Other features and objects of the invention will appear in the followingdetailed description in conjunction with drawings, wherein:

FIG. 1 is a front elevation view of the portable incubator of theinvention with the cover of the outer container closed and latched;

FIG. 2 is a cross-section of the incubator of FIG. 1 along the line 2 2,and shows the inner and outer insulated cotnainers resting one withinthe other;

FIG. 2a is a detail showing how the lid of the inner containerconductively and thermally engages the walls of the inner container;

FIG. 3 is an exploded View of FIG. l and shows the outer container withits cover in the open position and the inner container above the outercontainer. A portion of the inner container is shown broken away todisclose the interior thereof;

FIG. 4 is a top or plan view of the incubator of FIG. 1 and shows thehandle for carrying the portable incubator and the two portals whichalso serve as air vents for the outer container;

FIG. 5 schematically illustrates the electrical wiring for the portableincubator of the invention and shows the two sets of cords forindividually supplying electrical heating energy to the respectivecontainers.

Throughout the figures of the drawing the same parts are represented bythe same reference characters.

The portable, lightweight incubator of the present invention comprisesan outer container or box and an inner container or box 12 within whichthe infant rests. The outer container 10 has a main box-like bodyportion 11 and a cover 13 hingedly connected thereto at 14. A handle 16at the top of the cover 13 permits the entire incubator to be carried byhand. A pair of latches are provided to tixedly hold the cover 13 in itsclosed position. The four walls W and the cover 13 of the outercontainer are thin sheets of polished aluminum which rapidly conductheat and have excellent heat reflecting surfaces. These aluminum walls Wand the aluminum cover 13 are all in good thermal engagement as may benoted from FIGURES 2 and 3 which show the cover provided with edge areaswhich conductively contact the metal walls. The inner container includesfour walls W' and a cover or lid 17 all made of thin sheets of polishedaluminum having the same characteristics of rapid heat conduction andexcellent heat reflecting surfaces as the walls of the outer container.The lid 17 is provided with spaced aluminum extensions 18 along its twolong sides for conductively engaging the top portions of the aluminumwalls W' to enable heat to pass rapidly as possible from the lid 17 tothe walls W. Both outer and inner containers 10 and 12 are surroundedwith lightweight but effective heat insulation 19, such as styrene orvacucel, preferably composed of a multiplicity of air cells contained incompressed plastic material. In the closed position of each container,the aluminum cover or lid is in good thermal conduction contact with thealuminum walls thereof.

The cover 13 of the outer cotnainer 10 is provided with a pair ofportals or vents 20 for enabling the air in the interior thereof to passtherethrough, and also any electrical wiring, as may be required forcontrol purposes -to pass therethrough. Similarly, the lid 17 of theinner container 12 is also provided with a pair of portals or vents 21for the same purpose. The inner container 12 as shown in the explodedview of FIG. 3 provides a vent space between the tops of the aluminumwalls W and the lid 17 at each end of the lid 17 when the lid 17 is inclosed position on the walls W', due to the V-shaped nature of the lid.If desired, the lid 17 of the inner container may be hingedly fastenedto one long side of the top wall of the inner container in the samemanner as the cover 13 of the outer container is hingedly fastened toits container.

The inner container 12 is provided with a sheet metal bottom B uponwhich and spaced therefrom by an air space is an apertured sheet metalplate 22. The apertured sheet metal plate 22 is made to be appreciablythicker than the bottom B and the side walls W for supporting a matressor pad 23. Note FIGS. 2 and 3. The infant rests on the mattress or pad23 within the inner container.

Both the outer and inner containers are heated from separate sources ofelectrical energy. The heating unit for the outer container 10 is anysuitable means on the metal bottom thereof, as for example, a hot plateH sold under the trademark Hotray which is connected to a conventionalelectrical cord 24 in turn provided with a prongtype plug 25 forinsertion into the house mains supplying volts, 60 cycles, alternatingcurrent. The inner container 12 is provided with a conventionalelongated heating unit 26 mounted on top of and in a U-shaped depressionformed in the aluminum lid sheet 17. The heating unit is designed to beheated from a battery, such as a 12 volt battery in an automobile, bymeans of an electrical cord 30 having a suitable plug 27 for insertioninto the electric cigarette lighter outlet of the automobile. Obviously,the battery for heating the unit 26 need not Be intimately connectedwith the autmobile ignition system and the electrical cord 26 and plug27 represent any suitable electrical connection from the heating unit toa source of electrical energy such as a battery or dry cell that canfurnish the required voltage for about three hours.

When the inner container 12 is inserted into the outer container 10 thebottom B of the inner container rests upon and is heated by the heaterH. The air space between the bottom B and the apertured metal plate 22assures that the plate 22 does not rest directly upon the heater andhence does not produce hot spots above the mattress 23 such as whichmight occur if a direct stream of hot air flowed regularly against onespot. The uniformly spaced holes in the metal plate 22 assures that theradiant heat owing through the air space and through the holes in themetal plate 22 uniformly heats the mattress and the infant lying on themattress. The distance between the bottom B and the apertured plate 22of the inner container may be one inch,

One end of the outer container 10 is provided with means, such asbrackets or straps 28, for supporting a source of oxygen indicated at Owhich may take the form of a pressure tank of oxygen. The same end ofthe outer container 10 is provided with an oxygen entry opening 292,such as a nipple for connection of a hose from the source of oxygen. Thepressure tank is provided with the usual metering valve, flexibletubing, and dial mechanism (or flow meter), to determine, under control,the amount of oxygen which passes into the incubator and into the innercontainer. Since methods of achieving this result are known, no claimper se is being made to this particular feature as part of the presentinvention.

The electrical circuitry for the two heating units H and 26 are shown inFIG. 5. The heater H resting on the bottom of the outer container and incontact with the metallic bottom of the inner container may be aconventional type such as an A.C. heater, 250 watts, drawing 2.2 amperesof current, and suitable for use with 110-115 volts alternating currenthouse mains. The heater 26 for the lid of the inner container may alsobe a conventional type direct current heater, such as a 12 volt D.C.heater, 46 watts, drawing 3.75 amperes of current and suitably insulatedfrom an electrical standpoint from the aluminum lid 17. In circuit withthe 12 volt electrical wiring, there is provided a temperature sensingelement or probe 31 which, is adapted to be placed on the babys stomachto maintain the abdomen at a fairly precise temperature of 96 F. withinhalf a degree. This temperature sensing element may be a thermostatwhich opens the electrical circuit to the heater 26 whenever the skintemperature exceeds a safe value or may be a thermistor having a dcsiredtemperature coetlicient to increase the electrical resistance of thethermistor and reduce the current drawn by the heater 26 when the skintemperature rises and vice versa Such a thermistor may be one made byCole- Palmer of Chicago, Ill. or Fenwal 53600-0 thermistor with 71900probe made by Fenwal of Ashland, Mass.

A shielding window 32 in the main body of the outer container enablesthe viewing of a pair of thermometers 33, 34 on the inside of theincubator, one thermometer 33 measuring the wall temperature of theinner container and the other thermometer 34 measuring the ambient orair temperature of the inner container. The inner wall thermometer 33 ismounted on one wall W' of the inner container while the ambientthermometer 34 is connected by capillary tubing and a probe to theinterior of the inner container. This probe may hang or dangle in theinterior between the surrounding lwalls W from tubing extending throughone of the ports 21. The insulation 19 is removed at the location of thethermometers to permit visual inspection thereof from the outside of thethermometer. Obviously, if desired, the thermometers 33, 34 may be soarranged and suitably located on the lid 17 to permit visual inspectionthrough the portals 20 of the outer container. Since the details ofconnecting such thermometers to perform the above functions areconventional, no detailed illustration has been given in the interest ofsimplicity of illustration so as not to detract from the clarity of thedrawings.

Small signal lights 35, 36 are shown in FIG. 5 wired in conventionalmanner in parallel with the heaters H and 26 to afford visual evidenceof the fact that these heaters are electrically operative whenever suchis the case during operation of the equipment. These lights may belocated at any convenient place on the incubator. Thus the lights willturn on when their respective heaters are on, and will be olf when noelectrical current is being supplied to their respective heaters.

In the operation of the incubator of the invention when it is desired totransport an infant therein, the portable incubator is started up byenergizing the outer box heater H until the ambient temperature of theinner container 12 and the wall temperature of the inner container 12reach the desired temperatures 89 F. (but not exceeding 93.2 F.) and93.4 F., respectively, as measured by thermometers 34 and 33,respectively. At this point, the infant can be placed Within the innercontainer upon the mattress 23, the probe 31 placed upon the infantsstomach next to skin and the lid 17 closed. The controls using thetemperature sensing devices will maintain an abdominal skin temperatureof about 96.1 F. The outer cover 13 is then closed and latched, the plug25 disconnected from the house mains, and the incubator hand carried byits handle 16 into the heated ambulance at which time the innercontainer heater 26 is connected to the l2 volt car battery. The infantwill receive radiant heat from the -walls and lid of the inner containeruntil the ambulance reaches its destination at which time the incubatorcan be disconnected from the car battery and hand carried into thehospital or house.

By way of example only, the overall dimensions of the outer containerincluding cover 13 and insulation but excluding the oxygen tank may be22" long, 15 wide and high, while the dimensions of the inner containerincluding cover and insulation may be 18" long, 11.5" Wide and 10.5high. The weight of the incubator exclusive of oxygen tank may be about20 lbs. A prematurely born infant may weight anywhere from 2-5 lbs. moreor less.

Suitable apparatus may be incorporated or attached to the incubator ofthe invention for controlling conditions of humidity, and a portablelightweight suction machine operating on a l2 volt or 6 volt battery mayalso be incorporated in the design of the invention.

What is claimed is:

1. An incubator having inner and outer containers, said inner containerbeing adapted to support an infant therein, and individual heatingelements for said containers the interior walls of both said containersand said covers comprising thin metallic sheets providing rapid heatconduction and excellent heat reflecting surfaces, said metallic Wallsand cover of each container -being in thermal engagement with oneanother, there being insulation on the exterior surfaces of saidmetallic sheets, said electrical heating elements for said inner andouter containers having different power capabilities, the heatingelement for said outer container being designed for connection to houseelectrical power main while the heating element for said inner containeris mounted upon and heats one of said interior surfaces of said innercontainer and designed for a direct current battery source of electricalenergy, whereby radiant heat is provided by the interior walls and coverof said inner container upon energization of the heating element forsaid inner container.

2. An incubator having inner and outer containers, said inner containerbeing adapted to support an infant therein, and individual heatingelements for said container, both of said containers being provided withcovers, the walls and covers of both said containers comprising thinmetallic sheets providing rapid heat conduction and excellent heatreflecting surfaces of said metallic sheets, there being insulation onthe exterior surfaces of said metallic sheets, said electrical heatingelements for said inner and outer containers having different powercapabilities, the heating element for said outer container being mountedin the interior and on the -bottom of said outer container and -beingdesigned for connection to house electrical power mains while theheating element for said inner container is designed for a directcurrent battery source of electrical energy, said inner container havinga metallic bottom resting on the heating element for said outercontainer, and a temperature sensing device in circuit with the heatingelement of said inner container for controlling the temperature in saidinner container, both of said covers having air vents therein.

3. An incubator having inner and outer containers, said inner containerbeing adapted to Suport an infant therein, and individual heatingelements for said container both of said containers being provided withcovers, the walls and covers of both said containers comprising thinmetallic sheets lproviding rapid heat conduction and excellent heatreflecting surfaces, there being insulation on the exterior surfaces ofsaid metallic sheets, said electrical heating elements for said innerand outer containers having different power capabilities, the heatingelement for said outer container being mounted in the interior and onthe bottom of said outer container and being designed for connection tohouse electrical power main while the heating element for said innercontainer is designed for a direct current battery source of electricalenergy, said inner container having a metallic bottom resting on theheating element for said outer container and also having an aperturedplate mounted above and spaced from said metallic bottom for supportinga mattress, and a temperature sensing device in circuit with the heatingelement of said inner container for controlling the temperature in saidinner container, both of said covers having air vents therein, saidheating element for said inner container being mounted adjacent to theexterior surface of the metallic sheet constituting the cover for saidinner container, whereby an infant resting on said mattress will receiveradiant heat from the sheet metal walls and cover of said innercontainer when the heating element for said inner container isenergized, and means for measuring the wall and ambient temperatures ofsaid inner container.

4. An incubator having inner and outer containers, said inner containerbeing adapted to support an infant therein, and individual heatingelements for said container, both said containers being provided withcovers and exterior insulation for said containers and covers, atemperature sensing ydevice in circuit with the electrical heatingelement for said inner container for controlling the temperature in saidinner container, said temperature sensing device comprising a bodycontacting element adapted to contact the infants abdomen, saidincubator being portable and lightweight, the walls and covers of saidcontainers comprising thin metallic sheets providing rapid heatconduction and excellent heat reflecting surfaces, said insulation beinga plastic material provided with air cells, said covers having air ventstherein, said heating element for said inner container being of a sizecapable of being heated by a relatively low voltage battery, andthermometers for measuring the wall and ambient temperatures of saidinner container.

5. A portable incubator comprising a container adapted to support aninfant, said container having a heat source therefore, said containerhaving thin metal sheet walls and thin metal bottom and cover sheets,all in thermal engagement in the closed position of said incubator, saidmetal sheets being made of a material which rapidly conducts heat andhas interior surfaces which highly reflect heat, said heat source beingadjacent at least one of said metal sheets, and insulation on allexterior surfaces of said metal sheets, whereby said walls, bottom andcover are kept at a predetermined temperature during enerigization ofsaid heat source to prevent loss of radiant heat from the infant, asecond heat source positioned adjacent to the bottom sheet of saidcontainer and designed for energization by one type of current, rst heatsource being adjacent to the cover sheet of said container and designedfor energization by means of another type of current.

6. An incubator having inner and outer ccntainers, said inner containerbeing adapted to support an infant therein, and individual heatingelements for said inner container, the interior walls, bottom and coverof said inner container comprising metallic sheets providing rapid heatconduction and excellent heat reflecting surfaces, said metallic walls,bottom and cover of said inner container being in thermal engagementwith one another, there being insulation on the exterior surfaces ofsaid metallic walls and cover, said electrical heating elements for saidinner and outer containers having different power capabilities, one ofsaid heating elements `being adjacent said bottom wall and beingdesigned for connection to house electrical power mains while the otherheating element for said inner container is mounted upon the cover forsaid inner container and is designed for a direct current battery sourceof electrical energy, whereby the bottom, walls and cover are maintainedat a relatively constant temperature to prevent loss by radiantdeenergization of the infant within said inner container uponenergization of either or both of the heating elements.

References Cited UNITED STATES PATENTS 2,093,648 9/1937 Rice. 2,470,7215 1949 Pragel. 2,638,087 5/ 1953 Livsey. 2,641,248 6/ 1953 Armstrong.3,338,233 8/1967 Groshola et al.

FOREIGN PATENTS 827,769 2/ 1960 Great Britain.

WILLIAM E. KAMM, Primary Examiner

